After some changing to above Henry's answer, I got a tick with in a circle, I came here looking for that, so adding my code here.
.snackbar_circle {
background-color: #f0f0f0;
border-radius: 13px;
padding: 0 5px;
}
.checkmark {
font-family: arial;
font-weight: bold;
-ms-transform: scaleX(-1) rotate(-35deg);
-webkit-transform: scaleX(-1) rotate(-35deg);
transform: scaleX(-1) rotate(-35deg);
color: #63BA3D;
display: inline-block;
}
_x000D_
<span class="snackbar_circle">
<span class="checkmark">L</span>
</span>
_x000D_